diff --git a/lib/dgif_lib.c b/lib/dgif_lib.c
index fddc0d2..7a6ab9c 100644
--- a/lib/dgif_lib.c
+++ b/lib/dgif_lib.c
@@ -54,7 +54,7 @@ DGifOpenFileName(const char *FileName, int *Error)
     int FileHandle;
     GifFileType *GifFile;
 
-    if ((FileHandle = open(FileName, O_RDONLY)) == -1) {
+    if ((FileHandle = _open(FileName, O_RDONLY)) == -1) {
 	if (Error != NULL)
 	    *Error = D_GIF_ERR_OPEN_FAILED;
         return NULL;
@@ -81,7 +81,7 @@ DGifOpenFileHandle(int FileHandle, int *Error)
     if (GifFile == NULL) {
         if (Error != NULL)
 	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
-        (void)close(FileHandle);
+        (void)_close(FileHandle);
         return NULL;
     }
 
@@ -95,7 +95,7 @@ DGifOpenFileHandle(int FileHandle, int *Error)
     if (Private == NULL) {
         if (Error != NULL)
 	    *Error = D_GIF_ERR_NOT_ENOUGH_MEM;
-        (void)close(FileHandle);
+        (void)_close(FileHandle);
         free((char *)GifFile);
         return NULL;
     }
@@ -106,7 +106,7 @@ DGifOpenFileHandle(int FileHandle, int *Error)
     _setmode(FileHandle, O_BINARY);    /* Make sure it is in binary mode. */
 #endif /* _WIN32 */
 
-    f = fdopen(FileHandle, "rb");    /* Make it into a stream: */
+    f = _fdopen(FileHandle, "rb");    /* Make it into a stream: */
 
     /*@-mustfreeonly@*/
     GifFile->Private = (void *)Private;
diff --git a/lib/egif_lib.c b/lib/egif_lib.c
index f30b61b..18dc4a2 100644
--- a/lib/egif_lib.c
+++ b/lib/egif_lib.c
@@ -60,10 +60,10 @@ EGifOpenFileName(const char *FileName, const bool TestExistence, int *Error)
     GifFileType *GifFile;
 
     if (TestExistence)
-        FileHandle = open(FileName, O_WRONLY | O_CREAT | O_EXCL, 
+        FileHandle = _open(FileName, O_WRONLY | O_CREAT | O_EXCL, 
 			  S_IREAD | S_IWRITE);
     else
-        FileHandle = open(FileName, O_WRONLY | O_CREAT | O_TRUNC, 
+        FileHandle = _open(FileName, O_WRONLY | O_CREAT | O_TRUNC, 
 			  S_IREAD | S_IWRITE);
 
     if (FileHandle == -1) {
@@ -73,7 +73,7 @@ EGifOpenFileName(const char *FileName, const bool TestExistence, int *Error)
     }
     GifFile = EGifOpenFileHandle(FileHandle, Error);
     if (GifFile == (GifFileType *) NULL)
-        (void)close(FileHandle);
+        (void)_close(FileHandle);
     return GifFile;
 }
 
@@ -118,7 +118,7 @@ EGifOpenFileHandle(const int FileHandle, int *Error)
     _setmode(FileHandle, O_BINARY);    /* Make sure it is in binary mode. */
 #endif /* _WIN32 */
 
-    f = fdopen(FileHandle, "wb");    /* Make it into a stream: */
+    f = _fdopen(FileHandle, "wb");    /* Make it into a stream: */
 
     GifFile->Private = (void *)Private;
     Private->FileHandle = FileHandle;